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Full-Text Articles in Engineering
Permeability, Structural Changes, Flow Regime Transitions In Fuel Cell Catalyst Layers And A Model For Predicting Trapped Saturation For Two-Phase Flow In Porous Media, Karrar Takleef Alofari
Permeability, Structural Changes, Flow Regime Transitions In Fuel Cell Catalyst Layers And A Model For Predicting Trapped Saturation For Two-Phase Flow In Porous Media, Karrar Takleef Alofari
Dissertations, Master's Theses and Master's Reports
Proper water management in Proton Exchange Membrane (PEM) fuel cell is important to achieve high performance. Understanding the percolation of the produced water at the cathode catalyst layer (CL) is critical for any robust water management technique. In this study, an ex-situ experimental setup is used to study percolation in the CL at different injection rates and relative humidity (RH) conditions. The results show that increasing the flow rate force the liquid to flow through the bulk of the pores due to the dominant viscous effect. On the other hand, at low injection rates, the capillary becomes dominant and liquid …
Dynamics Of The Phase Coupling For Flow, Heat And Mass Transfer In Conjugate Fluid/Porous Domains, Mahmoud Mohamed Mostafa Elhalwagy
Dynamics Of The Phase Coupling For Flow, Heat And Mass Transfer In Conjugate Fluid/Porous Domains, Mahmoud Mohamed Mostafa Elhalwagy
Electronic Thesis and Dissertation Repository
Porous media prevail in industry e.g. heat transfer equipment, drying, food storage and several other applications. Integrated in engineering, they form conjugate Fluid/Porous domains. Physical modelling requires characterizing the microscale heat and mass (moisture) transfer interstitially within porous media and their macroscale counterparts across regional interfaces. Characterizing turbulence and its effects on phase coupling is often needed too. The modeling literature survey shows phase coupling assumptions depending on empiricism, phase equilibrium and lack of generality. Modeling of the dynamic variations for the modes of phase exchanges, i.e. heat, mass and heat accompanying mass exchanges, on both scales and generic turbulent …
Numerical Modelling Of Species Exchange In A 3d Porous Medium: Modelling Exchange Within The Human Lung, Chelsea E. Johnson
Numerical Modelling Of Species Exchange In A 3d Porous Medium: Modelling Exchange Within The Human Lung, Chelsea E. Johnson
Electronic Thesis and Dissertation Repository
The volume-averaged oxygen transport equation is closed using a volume-averaged form of Fick’s law of diffusion between the air and tissue to simulate species exchange within the lungs’ alveoli using a computational fluid dynamics (CFD) 3D conjugate domain model. Pore level simulations of a terminal alveolated duct are used to determine that the transport of inhaled oxygen from the cluster inlet to the alveolar walls is diffusion dominated. The resistance to oxygen diffusion into the tissue is found to be a function of the tidal volume and tissue transport properties, with a maximum respiration frequency at which the full amount …